Talking Fukushima One Year On

Now that the American Nuclear Society Fukushima report is out, here are a few additional notes.

First of all the full report is available either in sections or as an all-in-one PDF file from the special ANS Fukushima web site.

Second, you can watch the full one-hour long streaming video of the National Press Club event held March 8 by clicking here.

Third, I had an opportunity to talk via phone with the four members of the commission who participated in the press event March 8 to get some insights into their views. I’ve added in some of their remarks from the press conference. I live ‘tweeted” it so I combined the two sessions in this blog post. Here’s a summary of what they had to say.

The co-chairs of the ANS Commission are Dale Klein, the former chairman of the U.S. Nuclear Regulatory Commission and Michael Corradini, a senior faculty member (nuclear / mechanical engineering) at the University of Wisconsin (bios of both men here).

Klein prefaced his remarks by saying that one of the purposes of the ANS report is to set aside misinformation about Fukushima. He added that the purpose of the ANS report is not to affect policy and procedures at regulatory agencies, but to say what we know, and don’t know, with technical and scientific accuracy.

“ANS has an obligation to set the record straight.”

Klein, who worked in several senior positions in the federal government as a presidential appointee, has a firm grip on getting his message across in a matter of a few words. He starts by pointing out that no one has died from radiation exposure at Fukushima and that the health effects from radiation exposure are too small to measure.

“Fukushima was no Chernobyl.”

50 mile hike

One of the most contentious and still least understood events that took place from the U.S. point of view is the declaration March 16, 2011, by Gregory Jaczko, the current chairman of the NRC, ordering all Americans to evacuate to a distance of 50 miles from the Fukushima reactor complex. Klein and Corradini, speaking for the ANS Commission as a whole, said the technical basis for that decision is still unclear and that they remain “puzzled” by it.

While debate over the reason the Jaczko’s statement continues, anti-nuclear groups have seized on it calling for the current 10 mile evacuation standard in a reactor emergency planning zone (EPZ) to be expanded to 50 miles. Klein’s response to that viewpoint is that a very large evacuation zone could create more problems than any level of safety achieved by declaring it.

“Sheltering in place” is a viable strategy in many instances.”

Corradini says a 50 mile hike is not a logical approach to the problem.

“The EPZ should be risk informed and not an arbitrary distance. The technical basis for the NRC’s 50 mile evacuation order for Americans was based on incorrect information.”

That information was a report that the water in the spent fuel pool at Fukushima reactor #4 has boiled off and that the entire contents of the pool had vaporized spewing radioactive materials into the atmosphere. This report turned out to be completely untrue. The spent fuel was never uncovered by water and suffered no damage from the hydrogen explosion that wrecked the outer containment building.

The hydrogen did not come from the spent fuel pool, but rather leaked into unit #4 from the adjacent reactor #3 which is believed to have suffered a partial meltdown inside the reactor pressure vessel.

Paul Dickman, the staff director for the ANS Commission, said the NRC transcripts of conversations during the early days of the Fukushima crsis show the effects of the “fog of war” where incomplete information coming from Japan contributed to difficulties in deciding how to respond.

Returning to the issue of what’s been learned from Fukushima, Corradini said that nothing that has been learned from the experience at Fukushima shows that U.S. nuclear reactors are unsafe.

Design basis issues

Cooradini said, anticipating the NRC’s action, that risk-informed regulations can help plan for unexpected events and mitigate their consequences. He points out that low probability, high consequence events require multiple “defense-in-depth” measures to deal with events like station blackout where off-site power is lost.

This point also gets at the definition of design basis. The ANS Commission report points out that TEPCO, the utility that owns and operated the Fukushima reactors, had multiple opportunities to build better defenses against tsunami events. A stone marker dated 869 AD was found at Fukushima which clearly showed the extent of waves from a 1:1000 event reaching much higher than elevation above sea level of the Fukushima site.

Corradini said there is a lesson learned there for the NRC which is that it should periodically review the design basis for extreme events like seismic activity and flooding. How much protection is enough? Klein says that cost-benefit analysis is useful because it will help explain how much safety is being added for the additional cost of proposed regulatory measures.

What about spent fuel?

Klein said that with all the focus on wet storage of spent fuel at the nation’s 104 reactors, it is important to point out the Department of Energy’s Blue Ribbon Commission has called for the creating of an interim storage facility for it. In terms of priorities, he says DOE’s plan to simply move the oldest fuel first isn’t the best approach. Instead, he says the fuel that should be moved first is what’s left from decommissioned reactors. It’s an expense in terms of security and should be the first material to be moved to an interim site.

Second. fuel should be moved that would otherwise require a utility to expand its wet or dry storage facilities. Relieving utilities of the burden of building new on-site storage should be a priority. He added that the “right of first pickup” is something that could be sold between utilities depending on their needs.

Any feedback from Japan?

It is too early to know what the Japanese nuclear community thinks of the ANS Report. In Japan ANS Commission member Akira Tokuhiro, rolled out a presentation at the Foreign Correspondents Club on Friday March 9. In a telephone call to this blogger from Japan a few days before the press event, Tokuhiro said that mistrust of the government runs deep and will be a significant impediment to efforts to restart the nation’s reactors. As of March 10, 52 of the 54 units are shut down and the other two are expected to be shut down within the next 30 days. The 54 reactors supply 30% of Japan’s electricity.

The Los Angeles Times confirms his view that the “insidious legacy may be a shaken trust in government.”

The newspaper reported, “Many Japanese feel they’ve been lied to by their government,” said Mitsuhiro Fukao, an economics professor at Keio University in Tokyo who has written about the public loss of trust. “In a time of disaster, people wanted the government to help them, not lie to them. And many wonder whether it could happen again.”

Jacopo Buongiorno, a member of the ANS Commission, and a professor of nuclear engineering at MIT, said that the Japanese nuclear authorities and the government have been “even more forceful” in their critique of the design basis issues that contributed to the disaster.

Klein noted that the ANS Commission had good cooperation from Japanese sources and TEPCO. The utility provided Klein with a four-hour briefing on what it knew and when at various stages in the crisis.

According to the NRC two of the orders apply to every U.S. commercial nuclear power plant, including those under construction and the recently licensed new Vogtle reactors.

The first order requires the plants to better protect safety equipment installed after the 9/11 terrorist attacks and to obtain sufficient equipment to support all reactors at a given site simultaneously.

The second order requires the plants to install enhanced equipment for monitoring water levels in each plant’s spent fuel pool.

The third Order applies only to U.S. boiling-water reactors that have “Mark I” or “Mark II” containment structures. These reactors must improve venting systems (or for the Mark II plants, install new systems) that help prevent or mitigate core damage in the event of a serious accident. Plants have until Dec. 31, 2016, to complete modifications and requirements of all three orders.